Dishwasher



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JAMES O McMxLLAN I Y Z9 I sa I A i!" 30 www ATTORNEY United States Patent Office 3,062,226 Patented Nov. 6, 1952 3,662,226 DISHWASHER llames 0. McMillan, 1223 Jackson, Wichita, Kans. Filed Feb. 5, 1959, Ser. No. 791,497 4 Claims. (Cl. 134-112) This invention relates in general to dishwashers and in partcula-r to a dishwashing machine in which a basket of soiled dishes is positioned above a friction driven spray head; a motor driven pump, the water supply, a detergent supply, and a drain valve being brought into operation at predetermined times by a fluid controlled timer, manually set into operation prior to each washing cycle.`

This is an improvement over the device shown in my Patent No. 2,669,999, issued February 23, 1954, for Dishwashing Machine, wherein the jet members are rotated by the force of the liquid discharging therefrom, said liquid being supplied by city pressure, no pump being employed.

The objects of my invention are:

First; to provide a dishwasher in which I employ a motor operated pump to force water from a sump in the dishwasher through a rotatable spray head onto dishes in the chamber of the dishwasher over the spray head.

Second; to provide a new design in a freely rotatable spray head located above the pump and a friction drive between the pump and the spray head.

Third; to provide adjustable end jets in the rotatable spray head for adjustment to retard the rotation of the spray head to desired speed.

Other objects and advantages as well as the construction and operation of my invention will be better understood by reference to the following drawings in which:

FIG. l is a vertical, transverse, cross-sectional View through the dishwasher with parts in section and broken away for clarity of illustration, showing the pump and spray.

FIG. 2 is a fragmentary, enlarged, sectional view through the pump with a fragmentary portion of the motor head.

FIG. 3 is an enlarged detailed cross sectional view of the spray head and friction driving means therefor, parts being shown in elevation.

Referring now to the drawings by numerals of reference, in FIG. l, a cabinet is formed of upper portion 1 and lower skirt 2, suitably joined at 3 with sump 4. Access to opposite sides of the cabinet may be achieved by use of vertically telescoping doors 7 substantially as described in my Patent No. 2,669,999, the upper cabinet and doors forming a washing chamber 8.

The cabinet may be secured to suitable counters on which dish baskets may rest for feeding to and discharge from racks 10 in the dishwasher. Suitable legs 11 are secured to the lower skirt 2.

Pump and Rotatable Spray Head The pump is driven by suitable motor 12 held by fastening members 13 passing through motor end plate 14, sump bottom 4 and pump base 15 (see FIGS. 1 and 2).

Motor shaft 16 extends through motor end plate 14 in which bearing 17 is located and is suitably sealed at 18 in relation to the stationary pump base 15. An impeller 19 is secured to the shaft 16 and the upper end of shaft 16 carries freely rotatable spray head 20, rotated by friction with nut 21 on shaft 16 when the force of the liquid passing through the spray head raises same into contact with the rotating nut 21.

The stationary pump base 15, has upstanding lugs 22 against which peripheral ange 23 of pump body 24 bears, forming liquid passages 25 from the periphery of the pump base to the impeller 19. The pump body 24 is held in place by suitable fastening members 26 for rapid removal thereof for cleaning and maintenance. The interior of the pump body 24 is provided with spiral vanes 27 to guide the water to the rotating spray head 20.

To provide for removal of any water before it leaks past the seal 18 to cause damage to the motor, I provide on shaft 16, a water slinger disc 28, located in stationary pump base 15 just above the motor end plate 14, the latter being provided with an annular groove 29 and a drain outlet 30 leading from the groove 29 to the outer periphery of the motor end plate. (See FIG. 2.)

A removable screen or strainer 31 surrounds the pump -assembly which may be quickly a-nd easily disassembled for cleaning and servicing.

The rotatable spray head 20 comprises an elongated hollow member having a plurality of transverse slotted openings 32 and arcuate end configurations 33 with slotted openings 34 parallel with the longitudinal axis of the elongated hollow member. A space 21' is provided between the spray head and nut 21 and the spray head is free to rotate on end of the motor shaft 16 and is actuated at a slow speed by friction between the motor driven nut 21 and the hub of the hollow member. (See FIG. 3.) The pressure of the liquid entering the rotatable spray head forces said spray head upwardly against the rotating nut 21.

End plugs 26 are provided on the spray head 20 and have apertures 20" for spray discharge of liquid in a jet stream, adjustment of the plugs at a predetermined angle causing the discharging jet to retard the Speed of rotation of the spray head. It has been found that a jet of Water discharging from a rotatable spray head at too great a speed will lose some of its eiiiciency in the decreasing force of the water spray. Therefore, the end jets are employed, discharging at an angle opposite to the direction of rotation to slow down the rotatable spray head.

Washing and rinsing of dishes in the racks above the spray head are accomplished when the motor and pump are actuated, the water being drawn from the sump. Water enters the cabinet to spray over the dishes and fill the sump through upright conduit 35 and overhead conduit 36 with spray outlets 37. This will be explained more in detail later.

Water Control Valve passing to upright conduit 35 and overhead conduit 36 With spray outlets 37.

Detergent Dispenser An inverted detergent container 84, held by clamping members 84 is positioned above the valve body 64. A detergent passage $4 is adapted to receive detergent from the detergent container 84 for delivery to the washing chamber 8, a detergent displacement piston 88 resting on top of stem 69 aiding in controlling the amount of detergent released to passage 84".

Above the valve body 64 is half-round section 93 to which manual control lever is pivotally secured. A collar 96 is secured to the valve stem 69 and roller 97 pivotally carried by the lever 95 is received by the collar 96, whereby positive engagement is achieved between lever 95 and stem 69 regardless of any turning move- 3 ment of the stem 69. A suitable ball knob 98 may be used on one end of the control lever.

Alternate Construction for Use With City Water Pressure for Rinsng This dishwasher may be used to effect rinsing by use of the water in the sump, the motor operating to pump said water for spraying and rinsing purposes, or, by use of an auxiliary spray and a modified form of drain mechanism, city water pressure may be used for spraying purposes providing fresh water for rinsing at all times.

-In the alternate construction I provide a horizontal Spray tube 36' with spray outlets 37 positioned just above the rotatable spray head 20, said spray tube 36 connecting at the bottom of upright conduit 35, which in turn is connected to offset connector 77 from the valve body 64.

- Operation In operation, dishes are placed in baskets which are slid from a counter into the washing chamber 8 onto racks 10'. When in position, the doors 7 are closed and control lever 95 is depressed, setting otf a number of automatic operations.

When the pump and pump motor are set in motion and the pinnp receives its water supply from the liquid in the sump 4, the impeller 19 drives the water upwardly and out through slotted openings 32 and 34 in rotatable spray head 20. The spray head is rotated merely by friction with the nut 21 on shaft 16. A retarding rotation means is provided by end plugs through which a. jet of water discharges at an angle counter to the direction of rotation. These end plugs may be adjusted for desired speed of rotation. The screen 31 surrounding the pump assembly prevents entry thereto of food particles and may be cleaned Periodically.

From the foregoing it will be apparent that I have provided a compact and completely coordinated dishwashing apparatus where a plurality of related functions are correctly timed for orderly operation. Simple adjustments may be made in various elements for differences in conditions which may exist at specific locations where the dishwasher is installed, or where conditions differ in requirements for use of the dishwasher.

It is obvious that changes in form, proportion and details of construction may be resorted to without departing from the spirit of my invention and I reserve al1 rights to such changes as come within the scope of this specification and the claims Ywhich follow.

What I claim as new and desire to secure by Letters Patent is:

1. A dishwasher comprising a washing chamber, means for positioning articles to be washed in the washing chamber, a liquid receiving sump below and opening to the chamber, means for supplying washing liquid to the washing chamber, said washing liquid gravitating to the sump, a pump, a fluid inlet to the pump from the sump, means for driving the pump, a spray head rotatably supported in the washing chamber above the sump, said means for driving the pump including a shaft extending through and above'the pump, said spray head being journalled about said shaft but normally disengaged from driving relationship therewith, an outlet from the pump to the spray head, the liquid from the pump being forced through the spray head for discharge against the articles in the Washing chamber, the liquid pressure urging the spray head into frictional drive position on the shaft, and means for draining the liquid from the sump.

2. A dishwasher comprising a washing chamber, means for positioning articles to be Washed in the Washing chamber, a liquid receiving sump lbelow and opening to the chamber, means for supplying washing liquid to the washing chamber, said washing liquid gravitating to the sump, a pump, a fluid inlet to the pump from the sump, means for driving the pump, a freelyrotatable spray head supported in the washing chamber above the sump, said means for driving the pump including a shaft extending through and above the pump, said spray head being journalled about said shaft but normally disengaged from driving relationship therewith, a friction drive between said shaft and the spray head operable to rotate said spray head only when water pressure through said spray head raises same into friction drive position, and an outlet from the pump to the spray head, the liquid from the pump being forced through the spray head for discharge against the articles in the washing chamber as the spray head rotates, and means for draining the liquid from the sump.

3. A dishwasher comprising a washing chamber, means for positioning articles to be Washed in the Washing chamber, a liquid receiving sump below and opening to the chamber, a pump, a fluid inletrto the pump from the sump, means for draining liquid from the sump, a shaft extending vertically from the pump and rotatable therewith, a spray head in the washing chamber above the pump and freely rotatable and vertically movable on said shaft, a friction member on the upper end of the shaft retaining the spray head on said shaft, the upper surface of the spray head adjacent the friction member being normally free of said friction member, an outlet from the pump to the spray head, the liquid from the pump being forced through the spray head to raise said spray head vertically into frictional engagement with the friction member on the shaft and to discharge from said spray head against the articles in the washing chamber.

4. The structure as specified in claim 1, including an adjustable spray nozzle at each end of the sprayV head, the direction of the spray discharging from each nozzle `being opposite to the normal direction of rotation of said spray head and retarding the speed of rotation of the `spray head.

References Cited in the file of this patent UNITED STATES PATENTS Jackson Mar. 15, 

